Maybe that was the problem. In 5th a balanced, combined arms list just didn't work*. Trukks were actively a death trap and big boys mobs - while they were more survivable in movement - would get wiped out as soon as they hit combat, thanks to morale casualties. Interestingly, BW Brigade and nob bikers - both units I never fielded - were big causes of the anti-ork sentiment that meant putting my old ork army on the table meant taking an immediate sportsmanship hit, regardless of how I acted or how badly I lost.
There was some good in that book, true. Being able to shift MANz to troops was good. Being able to create a bike army was good (though I personally never did, but it was a good option to have). The SAG was a cool model (but never did more damage to the enemy than to my army when I fielded it). Deffkoptas were awesome if fragile, and lovely models just screaming for a proper multi part kit.
But for that we lost some really cool, effective and colourful units. The painboss and especially his cybork retinue, skarboyz, proper looted tanks, buggies with spikes & blades (never did much themselves, but watching the enemy tear themselves to pieces attacking them was always hilarious), properly customisable nobz in mobs.
* - maybe more accurately, I could never make it work.
I don't have any experience past 5th, but it seemed to me that a balanced force works better for some factions than others. For us, I think our lack of durability behooves us to take extremes to mitigate all the devastating answers most races can bring to the table. And the rules in 5th seemed designed around other races, causing us collateral damage, like being fearless and losing in CC. Clearly to balance berzerkers in CC but it always punished us because we'd "lose" by taking more wounds, IIRC.
When I think back to orks, I think we're a race that "asks a question" versus offering answers, in the parlance of MMA, or to say that we offer a lot of threats but not a lot of responses. For example, tankbustas are (or were) pretty ineffective at actual tankhunting, with negative rules for them and offering nothing but S8 to try and deal with AV14. Mediocre range, no survivability, kind of expensive too. In the end most of us recommended CCing heavy vehicles with klaws and leaving the bustas at home, or shooting at light targets.
I remember when I started my fish'ead army, and suddenly I had serious firepower. S10, long range. Actually hit a target without saturation firepower. My enemy respected my firepower. To be fair everyone respected my lootas too. And the SAG even though it was
useless an active threat against myself. The threat of it made the opponent behave themselves. But anyway I had all kinds of specialized & effective answers against any kind of threat.
Contrast that when I'm running Green Tide or Kan Wall, and the strategy is usually to try and cross the table in one piece and CHARGE. Hell if I was running BW spam the strategy is... cross the table in one piece and CHARGE!. If I was running a firepower list, the strategy was... cross half the table in one piece to get in range, and fire. And then charge anyway.
I have to say though, I never had any serious anti-ork sentiment when I was playing people outside my normal play group. Except against nob bikers though. They were like a boogeyman at some point. We could get pretty creative with wound allocation too, but everyone did that, so you can't really complain. I do remember my SAG nailing someone's special character and a tank on the first turn, first thing I did (skipped move) and I just rolled I think double 6s or whatever it was that just removed whatever it hit that was in play. He was salty. SAG never did anything useful in any game ever again though. I still took it, because damnit I loved it, but the devs had no idea how to balance that thing. They costed it on the average of its potential, when it needs to be steeply discounted because of the highly random effect. To make a comparison with MTG again, long ago they figured out that cards with random effects or choose-your-fate were bad, so they're costed lower than spells that actually do the thing you want reliably. Other games figured that out too. In FoW Italians and Romanians have randomized quality for their infantry, but they're not priced like fearless vets.
I don't miss skarboys, but everything else, for sure. Especially taking spikes & blades on my lone buggy, ramming it into gaunts.